[sgarland]

It depends on your constraints. If you’re limited by RAM, arrays make a lot of sense for certain applications. If you need Python’s buffer protocol, again, they make a lot of sense.

As to deques, yes, they have specific uses, and being slightly smaller isn’t usually a selling point for them. My point was that I have seen many cases where an incorrect data structure was used, because a list or dict was “good enough.” And sure, they generally are, but if the language ships with other options, why wouldn’t you explore those?